Casing having light-transmitting closure



July 24, 1928. I 1,678,137

- H. A. DOUGLAS CASING HAVING LIGHT TRANSMITTING CLOSURE .Filed July 2, 1927 amaz w Patented July 24, 1928.

" IT D "ST HARRY A. DOUGLAS 0F BRONSQN, IVIICl-IIGAN.

- ensure HAVIIiTG Liennanrins amtrme cnosnnn.

Application filed Inly 2,

My invention relats to casings which are provided with. light transmitting closures for the purpose of transmitting light from the interior of the casing to. the exterior of the casing or from the exterior of the casing to the interior. thereof, and comprises a body part, alight transmitting closure, a frame for the closure, and a closureretaining member positioned to hold the closure in assembly with the frame. the retaining member and body part having engaging portions that hold the closure frame in assembly with" the casing body.

In the preferred el'nbodiment of the invention the retaining member is in the form of a ring of spring metal which is bent to hold the closure and its frame in assembly by springpressure, the ring desirably engaging the closure at spaced apart places and. having a part engaging the frame between these places, the ring being spaced from the closure betweenits places of engagement with the closure in order that it may exert spring pressure upon the frame, and, consequently, spring pressure upon the closure. taining ring is provided with a portion between its places of engagement with the closure that engages a portion upon the body part of the casing in a manner to press this body part and the closure frame together whereby the assembly of the three casing parts, the body part, the frame and the closure, is completed. The body part of the casing is desirably formed with bayonet projections and the portions of the retaining member that are engaged with the casing body are formed with bayonet slots or channels that'receive said projections.

The invention will be more fully explained in connection with the accompanying drawing in which Fig. 1 is a longitudinal section of a casing which is shaped to hold an.

incandescent lamp whose light passes through the closure of the casing; Fig. 2 is a sectional view on line 2 2 of Fig. 1; Fig. 8 is a sectional view on line 3-3 of Fig. 1, on a larger scale; Fig. l illustrates the body part of the casing in perspective and in separate relation fromthe closure frame and retaining ring, which are shown in section, and the closure which is shown in elevation and in assembly with the frame; and 5 is a perspective view of the re taining ring.

The body part 1 of the casing is shown of concave form. It may be made of metal The re 1927. semi n qzoaea i. y Q '5 and have its interior surface bright to constitutea reflector! The casing illustratedis shown asbeing adapted to contain an in candescentlamp 2so that light .will shine t ing is in'nnaterial in so far as theinvention is concerned. The lncandescentlamp 2 is detachablysecured toa socket 3 which is equipped with circuit terminals for includ-' ing 'the 'lamp in circuit." The remaining parts of the casing are the light transmit ting closure 4, preferably of glasspand' an 7 annular frame 5for this closure, said casing bod'y l'being at the rear'side of said closure 4. internal shoulder 6 which isat the rearside of'the closure 4 is seated uponan external shoulder 7 for'med upon the casing part 1 nearthe front thereof. The framefi has a forward internaljFshou'lder 8fiwhichf i3 rests uponthe flange 9 of thelight transmit ting closure 4. By means of my invention,

the shoulders 6 and 7 are spring pressed into engagement as are also the shoulder 8 and the front side of the closure at its flange 9. To this end I employ a retaining member that is preferably in the form of a res'ilient ring of spring sheet metal which is bent at diametrically opposite places to have two portions 10 and 11 which are engaged with one of the casing parts 4. 5, preferably the part 4, the ring being spaced apart from the casing part 4 between the engaging portions 10 and 11 whereby the portions of the ring, where thus spaced apart from the casing part 4, are free to be flexed perpendicularly to thegeneral plane of the closure 4 so that it may exert the desired spring pressure to maintain the three casing parts 1, 4t and 5 in assembly. The ring is provided with two rearwardly extending fingers 12 that are located between the ring portions 10 and 11 and which are located at and upon the parts ofthe ring which are spaced apart from the closure 4 and are flexible perpendicularly to the general plane of the closure. These fingers project against the inner and channeled side of the shoulder 6 and serve slightly to depress the portions ofthe ring contiguous thereto toward the closure 4, these ring portions thusexerting spring pressure upon the shoulder 6 through the intermediation of said fingers, whereby the closure 4; is yieldlngly maintained mengagement with the This frame "is formed with frame 5 but with sufficient spring pressure normally to prevent separation of said closure and frame. The ring is also equipped with catches that are in the form of fingers.

13 that are formed with bayonet slots or channels 1 1, these fingers also being located between the ring portions 10 and 11 and extending from parts of the ring "that are spaced apart from the closure 4. The casing body 1 is equipped with bayonet'projec tions 15 which are inwardly continued fromv the front rim of the casing body and which are received in the bayonet slots 14 whenthe frame 5 is seated upon the shoulder 'T and is suitably turned. The bayonet slots 1 1 and projections 15 are so disposed that when they are engaged, the ring will be placed under tensionby reason of such engagement whereby the casing parts 1 and 5 willbe pressed each toward the other to hold them While I have shown the casing body l as.

being deep enough to hold an incandescent lamp and have illustrated the closure 4 as being convex, it is to be understood that the invention is not to be thus limited nor is it to be limited to other precise details of construction illustrated and specifically described. i 4

Changes may. be made without departing from the invention. I

Having-thus described my invention, 1 claim:

A casing including a casing body; a light transmitting closure at the rearv of which sald body is disposed; an annular frame sur-- rounding the closure and having an internal shoulder at the front side of the closure and an additional in'ternalshoulder which is at and spaced apart-from the rear side of said closure; a resilient retaining, ring having, portlons flexibleperpendicularly tothe gen eral plane of said closure and interposed I between said'closure and the aforesaid ad-;

ditional internal shoulder of the annular frame; said ring having rearwardly extendlng fingers upon its aforesaldfiexible portions and pressingupon this shoulder to press the first-aforesaid internal shoulder upon thev front side. of the closurepand catches carried by said retaining ring "and engaging the aforesaidcasing body and holding it against said. annular frame. g

In Witness whereof, I'hereunto subscribe my name. i a f i f HARRY A. DOUGLAS. I 

